"Original Chip Set" is the first graphics chipset to come with the Amiga computers. OCS was used primarily from 1985 to 1992 and available on the Amiga 1000, 500 and 2000. It offers the most limited resolutions of the three available chipsets. It could display up to 32 standard colors, 64 EHB colors, or 4096 colors using HAM mode. It was later improved upon by ECS and then AGA.